Conventional surveillance or broadcast video systems are deficient in a number of different respects. For example, the conventional systems fail to provide a mechanism for combining a multiplicity of digitally encoded sources into a single data stream without the use of special reclocking or data-rate converter equipment or circuits. Such elements are required in order to accommodate the differing data rates of the various sources, or, if all sources are encoded at the same data rate, path-length differences and thus phase differences between sources.
Also, there does not exist today an all-in-one system capable of self-healing functionality that can directly accept and transport video, audio, camera control, and data signals simultaneously without adding additional devices to convert standard video such as NTSC, PAL, SDI and audio formats such as AES-EBU, SPDIF, balanced or unbalanced analog, and data formats such as RS232, RS422, etc., into a single protocol that is compatible with high speed serial digital transport over fiber optics.
Conventional surveillance or broadcast video systems also lack a built-in video test signal generator with multiple patterns at the source for performance verification and various system alignment tasks. Often, if a test signal is present, it is usually within the source itself, and limited to one pattern such as color bars. This is insufficient for all the tests that might need to be performed on the system.
Furthermore, the conventional systems also exhibit significant latency between the video image and the camera pan, tilt and zoom controls. Due to the latency, the user has difficulty controlling the pan, tilt and zoom functions of the camera system. The user executes a command to move a camera, but the system exhibits significant delay before movement is preserved on the video monitor. The latency causes the user to overcompensate all camera movements.
Accordingly, there is a need in the art for a high quality, flexible and inexpensive long distance fiber optic communication and control system for simultaneous transport of multiple broadcast or surveillance video streams from distant sources that maintains a digital format, but in uncompressed form, from input to output and that provides a means for testing and performance validation, while also supporting self-healing functionality.